Hey all....Lookin to get an engine for my 40-60 size low wing sport plane. I know the Tower .75 seems to be a hands-down good deal for price, performance, and service. I have an opportunity to pick up a used GMS .76 for $60 which has been bench ran only. I know GMS makes the Tower engines, but the GMS .76 is a ringed engine and the Tower .75 is ABC. I have seen one mention that the GMS is an entirely different engine versus the Tower. Besides the ringed/ABC difference, you guys think the two are basically equal? Part of me leans toward the new Tower engine for $35 more, a warranty and great service go a long ways! Price is important, so I am limiting myself to engines say under $125 or so. I guess that means, Tower, GMS(new or this used one), Super Tigre, Magnum are what I will be looking at. I know the Tower engines are backordered until January, but waiting is not that big a deal. Suggestions or other ideas are greatly welcomed. Thank you all in advance. Tom.

The GMS 76 has a Dykes type ring on the piston. That'll be a big surprise for you if you try to hand start it?

If your plane is .60 size the best you could do is to place .91 engine, it is the
same weight and consumes a bit more fuel but you have lot more power when
you needed it. And the Power is newer enough; the worse feeling is when
you feel you are underpowered, isn't it, not only in Aviation
The guys on RCU seems to agreed that there are many very good ones,
some are copies of the OS.91 some are not, but all seems to have pretty
descent Power-to-Weight ratio better than any .60 size.

Get the Magnum 91 XLS, way more power than the Tower 75 ( I have them both) and about as cheap too.

asmund....I did a search for the magnum engines, Hobby People seemed to be the only "National mail order" to carry them. Tower didn't list them either. Where did you get yours from? Were warranty/service issues handled in a good way if you had any? I have heard the Magnum engines are a copy of the O.S. engine. Is that correct? As always, thanks for the quick replies everyone! Tom.

Yes it looks just like the OS 91 FX but it is different on the inside, the OS is ringed and the Magnum is true ABC. I have never had a warranty issue on any of my engine, I fix them myself if I have a problem. I ordered mine 91 XLS from WWW.peakmodel.com and it cost only 88$, but just some days ago they bumped the price to 108$, still cheap though. From what I have been running this engine it seems to be just as great as the other engines I have from Magnum.

Asmund...Thanks for the link. I checked them out, looks like they carry the Sanye S91A, which is made by Magnum. Is that the engine you are running? Tom.

That's backwards . . . . Sanye is the company that makes the Magnum, SC, ASP, and Evolution glow engines.

Gotcha, that's good to know.

Yes, that`s the engine I have.

GMS engines are warranted and serviced by Hobby Services just like O.S. Max, Tower Hobbies, and Super Tigre. I had a GMS .47 that I ran too lean when the head gasket was leaking, and the crankshaft broke. I mailed it off to Hobby Services along with my receipt and had a brand new replacement engine in my hand exactly one week later.

Magnum engines are serviced by Global Hobby, and Global also has an excellent reputation. I've never had to send any of my Magnum engines in for service, so I can only comment on the good things I've read about Magnum engine support here on the forums.

Another line of engines that are not always at the forefront of many modellers' minds are the Super Kraft (SK) and JBA engine lines sold and serviced by http://www.kangkeusa.com These engine lines offer very good performance and value, and the folks at KangkeUSA likewise have a good reputation for service, support, and parts availability.

After having said all of that, I recently bought a Super Tigre G-61 ringed 2-stroke for my King Kobra. It was on sale at Tower Hobbies for $79.99 ($5 off), and I'm awestruck at the power, performance, and ease of break-in and tuning this engine offers. When you throw in a 3-year warranty backed by Hobby Services, I really have a hard time guessing why more folks aren't flying Super Tigres.

Not if it's the GMS .76 II............The II has a conventional ring and loads of compression on the combustion stroke...

You may be correct about there being a MK II?

Though in the description for the GMS 76 with remote needle valve, it still says "with Dykes ring"

However in the parts pictures, if you can believe them, it shows a regular piston/ring.

Maybe that's why they are sold out- to make room for the new ones? Just a guess.

I have a .76 (with the Dykes ring) and it runs like a champ. Good slow idle, instant throttle response- great power and its getting better as I run it (GMS take their time breaking in) I have it on my Hanger 9 .60 Super Stick. Excellent combo for general sport flying, IMO.


Keep an eye on ebay for a good deal on one- I paid $70 for mine NIB and shipped.